PR c++/91370 - Implement P1041R4 and P1139R2 - Stronger Unicode reqs

PR c++/91370 - Implement P1041R4 and P1139R2 - Stronger Unicode reqs
	* charset.c (narrow_str_to_charconst): Add TYPE argument.  For
	CPP_UTF8CHAR diagnose whenever number of chars is > 1, using
	CPP_DL_ERROR instead of CPP_DL_WARNING.
	(wide_str_to_charconst): For CPP_CHAR16 or CPP_CHAR32, use
	CPP_DL_ERROR instead of CPP_DL_WARNING when multiple char16_t
	or char32_t chars are needed.
	(cpp_interpret_charconst): Adjust narrow_str_to_charconst caller.

	* g++.dg/cpp1z/utf8-neg.C: Expect errors rather than -Wmultichar
	warnings.
	* g++.dg/ext/utf16-4.C: Expect errors rather than warnings.
	* g++.dg/ext/utf32-4.C: Likewise.
	* g++.dg/cpp2a/ucn2.C: New test.

From-SVN: r277929

gcc/testsuite/ChangeLog

@@ -1,3 +1,12 @@
+2019-11-07  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/91370 - Implement P1041R4 and P1139R2 - Stronger Unicode reqs
+	* g++.dg/cpp1z/utf8-neg.C: Expect errors rather than -Wmultichar
+	warnings.
+	* g++.dg/ext/utf16-4.C: Expect errors rather than warnings.
+	* g++.dg/ext/utf32-4.C: Likewise.
+	* g++.dg/cpp2a/ucn2.C: New test.
+
 2019-11-07  Peter Bergner <bergner@linux.ibm.com>
 
 	PR other/92090

gcc/testsuite/g++.dg/cpp1z/utf8-neg.C

@@ -1,6 +1,6 @@
 /* { dg-do compile { target c++17 } } */
 
 const static char c0 = u8'';		// { dg-error "empty character" }
-const static char c1 = u8'ab';  	// { dg-warning "multi-character character constant" }
-const static char c2 = u8'\u0124';	// { dg-warning "multi-character character constant" }
-const static char c3 = u8'\U00064321';  // { dg-warning "multi-character character constant" }
+const static char c1 = u8'ab';  	// { dg-error "character constant too long for its type" }
+const static char c2 = u8'\u0124';	// { dg-error "character constant too long for its type" }
+const static char c3 = u8'\U00064321';  // { dg-error "character constant too long for its type" }

gcc/testsuite/g++.dg/cpp2a/ucn2.C

@@ -0,0 +1,30 @@
+// P1139R2
+// { dg-do compile { target c++11 } }
+// { dg-additional-options "-fchar8_t" { target c++17_down } }
+
+const char16_t *a = u"\U0001F914\u2753";
+const char32_t *b = U"\U0001F914\u2753";
+const char16_t *c = u"\uD802";		// { dg-error "is not a valid universal character" }
+const char16_t *d = u"\U0000DFF0";	// { dg-error "is not a valid universal character" }
+const char16_t *e = u"\U00110000";	// { dg-error "is outside the UCS codespace" "" { target c++2a } }
+					// { dg-error "converting UCN to execution character set" "" { target *-*-* } .-1 }
+const char32_t *f = U"\uD802";		// { dg-error "is not a valid universal character" }
+const char32_t *g = U"\U0000DFF0";	// { dg-error "is not a valid universal character" }
+const char32_t *h = U"\U00110001";	// { dg-error "is outside the UCS codespace" "" { target c++2a } }
+#if __cpp_unicode_characters >= 201411
+const char8_t i = u8'\u00C0';		// { dg-error "character constant too long for its type" "" { target c++17 } }
+#endif
+const char16_t j = u'\U0001F914';	// { dg-error "character constant too long for its type" }
+const char32_t k = U'\U0001F914';
+#if __cpp_unicode_characters >= 201411
+const char8_t l = u8'ab';		// { dg-error "character constant too long for its type" "" { target c++17 } }
+#endif
+const char16_t m = u'ab';		// { dg-error "character constant too long for its type" }
+const char32_t n = U'ab';		// { dg-error "character constant too long for its type" }
+#if __cpp_unicode_characters >= 201411
+const char8_t o = u8'\U00110002';	// { dg-error "is outside the UCS codespace" "" { target c++2a } }
+					// { dg-error "character constant too long for its type" "" { target c++17 } .-1 }
+#endif
+const char16_t p = u'\U00110003';	// { dg-error "is outside the UCS codespace" "" { target c++2a } }
+					// { dg-error "converting UCN to execution character set" "" { target *-*-* } .-1 }
+const char32_t q = U'\U00110004';	// { dg-error "is outside the UCS codespace" "" { target c++2a } }

gcc/testsuite/g++.dg/ext/utf16-4.C

@@ -4,8 +4,8 @@
 
 
 const static char16_t	c0 = u'';		/* { dg-error "empty character" } */
-const static char16_t	c1 = u'ab';		/* { dg-warning "constant too long" } */
-const static char16_t	c2 = u'\U00064321';	/* { dg-warning "constant too long" } */
+const static char16_t	c1 = u'ab';		/* { dg-error "constant too long" } */
+const static char16_t	c2 = u'\U00064321';	/* { dg-error "constant too long" } */
 
 const static char16_t	c3 = 'a';
 const static char16_t	c4 = U'a';

gcc/testsuite/g++.dg/ext/utf32-4.C

@@ -3,13 +3,13 @@
 /* { dg-do compile { target c++11 } } */
 
 const static char32_t	c0 = U'';		/* { dg-error "empty character" } */
-const static char32_t	c1 = U'ab';		/* { dg-warning "constant too long" } */
+const static char32_t	c1 = U'ab';		/* { dg-error "constant too long" } */
 const static char32_t	c2 = U'\U00064321';
 
 const static char32_t	c3 = 'a';
 const static char32_t	c4 = u'a';
 const static char32_t	c5 = u'\u2029';
-const static char32_t	c6 = u'\U00064321';	/* { dg-warning "constant too long" } */
+const static char32_t	c6 = u'\U00064321';	/* { dg-error "constant too long" } */
 const static char32_t	c7 = L'a';
 const static char32_t	c8 = L'\u2029';
 const static char32_t	c9 = L'\U00064321';     /* { dg-warning "constant too long" "" { target { ! 4byte_wchar_t } } } */  

libcpp/ChangeLog

@@ -1,3 +1,14 @@
+2019-11-07  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/91370 - Implement P1041R4 and P1139R2 - Stronger Unicode reqs
+	* charset.c (narrow_str_to_charconst): Add TYPE argument.  For
+	CPP_UTF8CHAR diagnose whenever number of chars is > 1, using
+	CPP_DL_ERROR instead of CPP_DL_WARNING.
+	(wide_str_to_charconst): For CPP_CHAR16 or CPP_CHAR32, use
+	CPP_DL_ERROR instead of CPP_DL_WARNING when multiple char16_t
+	or char32_t chars are needed.
+	(cpp_interpret_charconst): Adjust narrow_str_to_charconst caller.
+
 2019-11-05  Tim van Deurzen  <tim@kompiler.org>
 
 	* cpplib.h: Add spaceship operator for C++.

libcpp/charset.c

@@ -1881,10 +1881,11 @@ cpp_interpret_string_notranslate (cpp_reader *pfile, const cpp_string *from,
 /* Subroutine of cpp_interpret_charconst which performs the conversion
    to a number, for narrow strings.  STR is the string structure returned
    by cpp_interpret_string.  PCHARS_SEEN and UNSIGNEDP are as for
-   cpp_interpret_charconst.  */
+   cpp_interpret_charconst.  TYPE is the token type.  */
 static cppchar_t
 narrow_str_to_charconst (cpp_reader *pfile, cpp_string str,
-			 unsigned int *pchars_seen, int *unsignedp)
+			 unsigned int *pchars_seen, int *unsignedp,
+			 enum cpp_ttype type)
 {
   size_t width = CPP_OPTION (pfile, char_precision);
   size_t max_chars = CPP_OPTION (pfile, int_precision) / width;
@@ -1913,10 +1914,12 @@ narrow_str_to_charconst (cpp_reader *pfile, cpp_string str,
 	result = c;
     }
 
+  if (type == CPP_UTF8CHAR)
+    max_chars = 1;
   if (i > max_chars)
     {
       i = max_chars;
-      cpp_error (pfile, CPP_DL_WARNING,
+      cpp_error (pfile, type == CPP_UTF8CHAR ? CPP_DL_ERROR : CPP_DL_WARNING,
 		 "character constant too long for its type");
     }
   else if (i > 1 && CPP_OPTION (pfile, warn_multichar))
@@ -1980,7 +1983,9 @@ wide_str_to_charconst (cpp_reader *pfile, cpp_string str,
      character exactly fills a wchar_t, so a multi-character wide
      character constant is guaranteed to overflow.  */
   if (str.len > nbwc * 2)
-    cpp_error (pfile, CPP_DL_WARNING,
+    cpp_error (pfile, (CPP_OPTION (pfile, cplusplus)
+		       && (type == CPP_CHAR16 || type == CPP_CHAR32))
+		      ? CPP_DL_ERROR : CPP_DL_WARNING,
 	       "character constant too long for its type");
 
   /* Truncate the constant to its natural width, and simultaneously
@@ -2038,7 +2043,8 @@ cpp_interpret_charconst (cpp_reader *pfile, const cpp_token *token,
     result = wide_str_to_charconst (pfile, str, pchars_seen, unsignedp,
 				    token->type);
   else
-    result = narrow_str_to_charconst (pfile, str, pchars_seen, unsignedp);
+    result = narrow_str_to_charconst (pfile, str, pchars_seen, unsignedp,
+				      token->type);
 
   if (str.text != token->val.str.text)
     free ((void *)str.text);